You’ve been watching what you eat, and yet the pounds refuse to budge. These secret diet saboteurs may be to blame.

You know how some sneakers are specifically engineered for workouts and others, it turns out, are suited for nothing more than making fashion statements? Well, foods are like that too. Some are dressed up to look like they’re good for you when in fact they’re anything but. When you’re trying to eat well, it can be maddening when unhealthful impostors—filled with sugar, fat, and sodium—undo your good work. Here’s how to spot and stop seven of them.

Energy Bars

Just because they come in a tiny package that says they’re loaded with vitamin and minerals, energy bars are not necessarily a healthy choice. In fact, “a lot of them are nothing more than glorified candy bars,” says Sari Greaves, RD, nutrition director for Step Ahead Weight Loss Center in New Jersey. “They can be packed with enriched white flour, high fructose corn syrup, and other sweeteners.” Many are high in saturated fat, too, and low in fiber. “And if you eat them in addition to meals,” says Greaves, “that’s an extra 300 to 400 calories in your day, which most of us can’t afford.”

Eat Smart:

If you’re replacing a meal with an energy bar, choose one with 200 to 300 calories; for a snack, shoot for 150 calories or fewer.

Opt for a bar whose ingredient list is short and begins with a whole grain such as brown rice, whole wheat, or whole oat flour.

Make sure your pick meets at least two of Greaves’s requirements: fewer than 15 grams of sugar, less than 2 grams of saturated fat, at least 3 grams of fiber, and at least 5 grams of protein.

If you can’t find one containing that much protein, add it yourself: Spread a low-calorie bar with a thin layer of peanut butter, or enjoy a glass of low-fat milk or a piece of low-fat string cheese with it. “Adding in the protein will help you feel more satisfied longer,” says Greaves.

Granola

Given that we use the word “granola” to describe healthy, outdoorsy types, it’s ironic that the yummy breakfast cereal is one of the least healthy ways to start your day. “Most have too much sugar and very little fiber. A healthy breakfast cereal should be the exact opposite,” says Keri Gans, RD, author of the forthcoming Small Change Diet (to be published by Gallery Books in spring 2011, amazon.com). With all the sugar it contains, just one cup of granola can easily top out at 600 calories, a third of the average woman’s daily allowance.

Eat Smart:

Gans recommends picking a cereal that has the same satisfying crunch as granola but contains more grams of fiber than sugar. Add a heaping tablespoon of nuts (try walnuts) and your favorite berry for sweetness.

If you just can’t give up granola, sprinkle a small amount (less than a quarter of a cup—that’s how unhealthy it is!) over low-fat or nonfat plain yogurt with a handful of blueberries or a half-cup of sliced strawberries.